PIA06920 - This approximate true-color image taken by NASA's Mars Exploration Rover Opportunity shows an unusual, lumpy rock informally named "Wopmay" on the lower slopes of "Endurance Crater." The rock was named after the Canadian bush pilot Wilfrid Reid "Wop" May. Like "Escher" and other rocks dotting the bottom of Endurance, scientists believe the lumps in Wopmay may be related to cracking and alteration processes, possibly caused by exposure to water. The area between intersecting sets of cracks eroded in a way that created the lumpy appearance. Rover team members plan to drive Opportunity over to Wopmay for a closer look in coming sols. This image was taken by the rover's panoramic camera on sol 248 (Oct. 4, 2004), using its 750-, 530- and 480-nanometer filters.